The present invention relates generally to containers such as cups and the like manufactured of plastic material. In particular, the present invention relates to the manufacture of one-piece foam sheet material cups. For some time cups have been manufactured of expanded polystyrene beads by the well-known steam chest process. This method of cup manufacture has the inherent disadvantage in that each container, if so desired, must be individually decorated by an elaborate and time consuming process. It was then discovered that oriented foam sheet material could be produced and decorated on one side similar to and by techniques used in the paper decorating industry. The decorated foam sheet material was then cut into rectangular shaped blanks which were then rolled into cylinders containing a single side seam. The cylinders were then placed on a mandrel with a portion of the cylinder protruding beyond the mandrel. The mandrel and the plastic foam sheet stock cylinder which it contained were then subjected to heat which in turn caused the foam sheet cylinder to shrink to the external configuration of the mandrel. A separate bottom closure has been used with the foam sheet cylinder to produce a two-piece container. Also, a one-piece cup has been produced by merely pressing the extra material, that protrudes beyond the mandrel, into a bottom structure. After the containers, such as cups for beverages, were produced by the above described method, the cups were then subjected to a separate rimming process which produced the familiar bead on the rim of the cup.